FIG. 1 depicts a conventional method 10 for fabricating conventional magnetic devices, such as read or write transducers. A photoresist layer is provided, via step 12. In some structures, for example for fabrication of poles, the photoresist layer may be desired to be thick, on the order of one to two microns or more. In other structures being fabricated, the photoresist layer may be thin. For example, the photoresist layer may be one-quarter to one-half micron. The photoresist layer typically covers substantially all of the substrate.
The substrate on which the magnetic device is fabricated includes a number of fields. The fields are typically aligned in an array of rows and columns. The fields of the magnetic device are exposed using a single mask in a particular sequence of fields, via step 14. The fields are generally exposed in groups in step 14. Typically, a single exposure using the single mask is performed for each group of fields. Thus, a pattern is defined in the conventional photoresist layer. Stated differently, the conventional photoresist mask is formed. For example, the mask features for structures including a main pole such as a perpendicular magnetic recording (PMR) pole, a shield, pads, connections, test markers, and other features may be formed in step 14.
The pattern in the conventional photoresist mask is transferred to form the magnetic device, via step 16. Step 16 might include removing a portion of the underlying magnetic recording device layer(s) and/or depositing additional layers for the features to be fabricated. For example, the PMR pole, shield, pads, connections, test markers, and other features may be formed while the appropriate mask remains in place. Thus, steps 12-16 may be taken when utilizing conventional photolithography in forming structures in the conventional magnetic recording device. Fabrication of the conventional PMR head 30 may then be completed.
Although the conventional method 10 may be used to form the conventional magnetic device, there may be drawbacks. In particular, there may be variations in the overlay of layers in the conventional magnetic device. For example, during fabrication of a perpendicular magnetic recording (PMR) pole, it is generally desirable for the main pole tip to be aligned with other structures in magnetic recording transducer. However, there may be some misalignments or offsets in the structures. For certain critical features, such as the PMR pole and shield, misalignments in the overlays may adversely affect performance of the conventional magnetic recording device.